An enormous amount of energy is wasted when cooled air escapes from supply ducts or when hot or cold attic air leaks into return ducts and visa versa. Studies indicate that as much as 30% of the conditioned air in an average central air conditioning system escapes from leaks in these ducts.
For forced air systems to be efficient, ducts must be airtight. A competent professional service technician will take great case in installing or repairing such ducts. Leaky ducts are difficult to find without experience and test equipment.
Even though still in use, the old standard duct tape is inefficient for sealing ducts. To provide a positive seal, current practice includes sealing the duct with “mastic.” Mastic is a duct sealant, usually water based and fiber reinforced. It is often provided in buckets or tubes for use in a caulking gun. Even with the use of mastic, tape is still required.
What is needed is an apparatus and application method that will provide a proper seal while reducing installation time of duct work.